Investigating the anti-filarial efficacy and molecular interactions of thiadiazol derivative: Insight from quantum chemical calculations, pharmacokinetics, and molecular docking studies

Abstract Parasitic infections such as lymphatic filariasis (elephantiasis) solely result from the infestation of a slender and thread-like worm. This condition precipitates swelling, often accompanied by skin alterations, potentially leading to substantial disability and disfigurement. Recent advancements in preventive measures for lymphatic filariasis encompass mass drug administration (MDA) involving antifilarial drugs. To that effect, this investigation employs an experimental and theoretical approach, utilizing the DFT/6–311++(2p,2d)/ωB97X-D level of theory, to evaluate the anti-filarial properties of a thiadiazol derivative, designated by the code (PTA). The comparative analysis of the spectroscopic data (FT-IR, UV, and NMR) was observed to be in good agreement. The geometry equilibration, it was observed that attributed to the influence of solvents and their properties, including the dielectric constant and polarity C18-S2 bond exhibited the highest bond length values 1.80208 (Å) in a gaseous environment. In the comparison of energy gaps, PTA_DMSO exhibited the smallest gap at 3.899 eV, while PTA_Water displayed a broader gap at 4.724 eV. PTA_Chloroform and PTA_Gas followed closely with energy gaps of 4.718 and 4.599 eV, respectively. The smaller energy gap observed in PTA_DMSO suggests higher reactivity and lower stability of the compound in this solvent. This finding underscores the potential efficacy of the ligand in DMSO as a promising drug candidate in this particular medium. From the molecular docking analysis shows the hydrogen bonds formed between 3VKL and PTA are four hydrogen bonds with a binding affinity of -4.6 kcal/mol, while with the two standard drugs, dimethylcarbamazine, one hydrogen bond with a binding affinity of -4.30 kcal/mol and albendazole with three hydrogen bonds with a binding affinity of -5.3 kcal/mol. Also, with 4BME protein, three hydrogen bonds with a binding affinity of -4.6 kcal/mol for PTA, one hydrogen bond for diethylcarbamazine with a binding affinity of -4.6 kcal/mol and two hydrogen bonds for albendazole with a binding affinity of -2.9 kcal/mol.